Over the last decade or so, for most businesses, it has become a necessity for employees to share data over local area networks. To improve efficiency, enhancements have added to a local area network such as remote wireless access. This enhancement provides an important extension in forming a wireless local area network (WLAN).
Typically, a WLAN features a wireless network interface card and a wireless access point (AP). The network interface card enables one or more wireless devices, such as a laptop computer or personal digital assistant, to communicate with the AP over the air. The AP operates as a relay station by receiving data frames from the network interface card and transmitting data from these frames to a fixed, backbone network. Thus, the AP supports communications with both a wireless network and a wired network.
Over the past few years, a number of WLAN standards have been developed. For instance, the revised 802.11 standard “Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) specifications” (IEEE 802.11, 1999) has been widely deployed. However, new features are continuously being developed to enhance the functionality of WLANs. For instance, WLANs are consistently being deployed with improved cryptographic functions and authentication protocols.
One problem associated with conventional APs is that such equipment is designed to support specific, existing wireless network standards. If a new feature or improvement is developed for the WLAN standard and support for this feature/improvement is desired, a new set of APs supporting the new WLAN standard must be deployed. This can be accomplished by deploying new APs operating in parallel with old APs or replacing the old APs with newer APs supporting both old and new WLAN standards. In either case, support for any new WLAN standard requires deployment of a whole new array of APs, which is quite costly and difficult to manage.
Another problem is that APs are generally installed in the plenium. In other words, network-forwarding intelligence is positioned outside the wiring closet. Hence, for many installations, APs are too troublesome to replace in order to reconfigure the network with minor, but useful, changes in the WLAN standard.